Subject: [patch] fix apparmor cache tempfile location to use passed arg v2

Merge from trunk revision 2142

This patch fixes problems in the handling of both the final cache
name location and the temporary cache file when an alternate location
is specified.

The first issue is that if the alternate cache directory location was
specified, the alternate directory name would be used as the final
location for the cache file, rather than the alternate directory +
the basename of the profile.

The second issue is that it would generate the temporary file that it
stores the cache file in [basedir]/cache even if an alternate cache
location was specified on the command line. This causes a problem
if [basedir]/cache is on a separate device than the alternate cache
location, because the rename() of the tempfile into the final location
would fail (which the parser would not check the return code of).

This patch fixes the above by incorporating the basename into the cache
file name if the alternate cache location has been specified, bases the
temporary cache file name on the destination cache name (such that they
end up in the same directory), and finally detects if the rename fails
and unlinks the temporary file if that happens (rather than leave it
around). It also has been updated to add a couple of testcases to verify
that writing and reading from an alternate cache location work.

Patch history:
  v1: first draft of patch
  v2: add testcases, convert PERROR() to pwarn() if rename() fails for
      placing cachefile into place.

For 2.8 branch:

Signed-off-by: Steve Beattie <sbeattie@ubuntu.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
This commit is contained in:
Steve Beattie 2013-07-29 09:52:18 -07:00
parent 09c2da3a69
commit 2fec3758ed
2 changed files with 19 additions and 6 deletions

View file

@ -1087,8 +1087,7 @@ int process_profile(int option, char *profilename)
if ((profilename && option != OPTION_REMOVE) && !force_complain &&
!skip_cache) {
if (cacheloc) {
cachename = strdup(cacheloc);
if (!cachename) {
if (asprintf(&cachename, "%s/%s", cacheloc, basename)<0) {
PERROR(_("Memory allocation error."));
exit(1);
}
@ -1107,7 +1106,7 @@ int process_profile(int option, char *profilename)
}
if (write_cache) {
/* Otherwise, set up to save a cached copy */
if (asprintf(&cachetemp, "%s/%s/%s-XXXXXX", basedir, "cache", basename)<0) {
if (asprintf(&cachetemp, "%s-XXXXXX", cachename)<0) {
perror("asprintf");
exit(1);
}
@ -1165,8 +1164,11 @@ out:
}
if (useable_cache) {
rename(cachetemp, cachename);
if (show_cache)
if (rename(cachetemp, cachename) < 0) {
pwarn("Warning failed to write cache: %s\n", cachename);
unlink(cachetemp);
}
else if (show_cache)
PERROR("Wrote cache: %s\n", cachename);
}
else {

View file

@ -12,7 +12,8 @@ fi
# fake base directory
basedir=$(mktemp -d -t aa-cache-XXXXXX)
trap "rm -rf $basedir" EXIT
altcachedir=$(mktemp -d -t aa-alt-cache-XXXXXXXX)
trap "rm -rf $basedir $altcachedir" EXIT
mkdir -p $basedir/cache
ARGS="--base $basedir --skip-kernel-load"
@ -158,3 +159,13 @@ echo "ok"
echo -n "Cache reading is skipped when parser in \$PATH is newer: "
(PATH=$basedir/parser/ /bin/sh -c "apparmor_parser $ARGS -v -r $basedir/$profile") | grep -q 'Replacement succeeded for' || { echo "FAIL"; exit 1; }
echo "ok"
echo -n "Profiles are cached in alternate location when requested: "
../apparmor_parser $ARGS -q --write-cache --cache-loc $altcachedir -r $basedir/$profile
[ ! -f $altcachedir/$profile ] && echo "FAIL ($altcachedir/$profile does not exist)" && exit 1
echo "ok"
echo -n "Cache is loaded from alt location when it exists and features match: "
../apparmor_parser $ARGS -v -r $basedir/$profile --cache-loc $altcachedir | grep -q 'Cached reload succeeded' || { echo "FAIL"; exit 1; }
echo "ok"